The Collaborative International Dictionary of English v.0.48:

Rescue \Res"cue\ (r[e^]s"k[-u]), n. [From Rescue, v.; cf.
   Rescous.]
   [1913 Webster]
   1. The act of rescuing; deliverance from restraint, violence,
      or danger; liberation.
      [1913 Webster]

            Spur to the rescue of the noble Talbot. --Shak.
      [1913 Webster]

   2. (Law)
      (a) The forcible retaking, or taking away, against law, of
          things lawfully distrained.
      (b) The forcible liberation of a person from an arrest or
          imprisonment.
      (c) The retaking by a party captured of a prize made by
          the enemy. --Bouvier.
          [1913 Webster]

                The rescue of a prisoner from the court is
                punished with perpetual imprisonment and
                forfeiture of goods.              --Blackstone.
          [1913 Webster]

   Rescue grass. [Etymol. uncertain.] (Bot.) A tall grass
      (Ceratochloa unioloides) somewhat resembling chess,
      cultivated for hay and forage in the Southern States.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Rescue \Res"cue\ (r[e^]s"k[-u]), v. t. [imp. & p. p. Rescued
   (-k?d);p. pr. & vb. n. Rescuing.] [OE. rescopuen, OF.
   rescourre, rescurre, rescorre; L. pref. re- re- + excutere to
   shake or drive out; ex out + quatere to shake. See Qtash to
   crush, Rercussion.]
   To free or deliver from any confinement, violence, danger, or
   evil; to liberate from actual restraint; to remove or
   withdraw from a state of exposure to evil; as, to rescue a
   prisoner from the enemy; to rescue seamen from destruction.
   [1913 Webster]

         Had I been seized by a hungry lion,
         I would have been a breakfast to the best,
         Rather than have false Proteus rescue me. --Shak.
   [1913 Webster]

   Syn: To retake; recapture; free; deliver; liberate; release;
        save.
        [1913 Webster]

WordNet (r) 3.0 (2006):

rescue
    n 1: recovery or preservation from loss or danger; "work is the
         deliverance of mankind"; "a surgeon's job is the saving of
         lives" [syn: rescue, deliverance, delivery, saving]
    v 1: free from harm or evil [syn: rescue, deliver]
    2: take forcibly from legal custody; "rescue prisoners"